In underground mining equipment, for example for coal mining, mining machines are used which are moved to and fro along a conveying device for the won coal. In mining equipment of this type, which can be up to 400 m in length, special pans are respectively arranged in the longwall end region, particularly in plough systems, so as to create the necessary structural space not only to be able to draw the plough into the longwall end region, but also to be able to arrange the drives for the plough in the longwall end region.
Corresponding special pans can consist, in particular, of so-called wedge pans, in which the machine guide acquires over the length of the trough pan an increasingly greater distance from the lateral element, and can consist of connector pans, in which the distance apart of the top strand and bottom strand is increased so as subsequently to redirect the chain around a chain wheel. Particularly in the case of these special pans, machine guide parts are used which can be detached from the trough pan to allow the installation, disassembly or repair of a plough, the replacement of sliding blocks on the plough, or the execution of other maintenance works on the plough. The fastening between the detachable machine guide part and the trough pan is realized by connector devices having a fitting and a counter fitting which can be locked in place with at least one retaining piece. The main field of application of the present invention relates to corresponding wedge pans and connector pans having detachable machine guides as the attachment part to the trough pan. However, the invention is also fundamentally applicable on other attachment parts which need to be detached from the trough pan.
A connector device of the generic type is known from DE 20 2004 001 476 U1, and the known connector device comprises, inter alia, hook elements in the lower region of the lateral elements, into which the removable machine guide part can be inserted by means of mounting pieces, so that in the lower region a separable hook coupling is obtained. With the retaining piece, in the connector device of the generic type, the attachment part and the lateral element have only to be prevented from swiveling apart, for which purpose the retaining piece is configured either as a screw-on locking bar or in the form of crescent-shaped bushings which project over the lateral part and, in turn, are secured against detachment by means of a screw bolt. Through the use of the hook coupling, the attachment of the machine guide can certainly be facilitated. However, the release, in particular, of the screw bolts is laborious and time consuming, and can be made considerably more difficult, in particular, by sticking of the bolts, the bushings or the locking bar.